Infinity Conjugate Distance Microscopic Objective Lens Stray Light Tester and Measurement Accuracy Adjustment Method

Abstract

The invention discloses a stray light tester for an infinite conjugate distance microscope objective lens, comprising: a light source for providing uniform illumination; an imaging device comprising an infinite conjugate distance microscope objective lens and a tube lens for imaging The black body target plate on the front focal plane of the conjugate distance microscope objective lens is used to provide black spots for the infinite conjugate distance microscope objective lens; the trinocular observation device, including a half-pentagonal prism that can move up and down, is used to observe and ensure the black spots during measurement The position is placed correctly; the filter device, the light emitted by the imaging device is filtered by the filter device and then output in the visible light band; the first aperture, which receives the visible light band and selects the light in the specific black spot image area of ​​the black spot in the visible light band for measurement ; Test integrating sphere, it carries out light equalization and attenuation to the measurement light that the first diaphragm that receives is selected; Photomultiplier tube, it is used for measuring the energy of the light of light equalization and attenuation through testing integrating sphere; The present invention has stray light source The advantages of reduction and high measurement accuracy.

Description

technical field [0001] The invention relates to the field of optical testing, more specifically, the invention relates to a stray light tester for an infinite conjugate distance microscopic objective lens and a method for adjusting test precision. Background technique [0002] At present, there are mainly two methods for measuring the stray light of the optical system, one is the black spot method (also called the surface source method), and the other is the point source method. Since the point source method uses a point-scanning method, the light must be collimated before entering the optical system, so for the central field of view, it is difficult to measure the reflection and scattering caused by the edge of the lens, the mirror frame and the lens barrel. Stray light. At the same time, for microscopic objective lenses with small aperture and large field of view, the parallel light illumination is very different from the real illumination, and the measurement results are ...

AI Technical Summary

Problems solved by technology

For low magnification and small numerical aperture microscopic objectives, the stray light tester of this microscopic objective can be well used for stray light measurement; for high magnification and large numerical aperture microscopic objectives, the stray light tester of this microscopic objective is There are certain defects, mainly for microscopic objectives with a numerical aperture greater than 1. If the blackbody target plate itself does not have scattering characteristics, it cannot guarantee that the numerical aperture of the illumination matches the numerical aperture of the objective lens; and the black-and-white contrast and Lambertian scattering characteristics must be guaranteed at the same time in the process The black body target plate is difficult to reach, which means that the device basically cannot be used for stray light measurement of microscope objectives with numerical aperture greater than 1

At the same time, the visual system composed of the spectroscopic element, reticle and eyepiece in the stray light tester of the microscopic objective lens is equivalent to a stray light source, which will affect the stray light measurement results of the microscopic objective lens

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